COMMUNITY RECOVERY FROM SIMULATED STREAMBED DISTURBANCE ACROSS A GRADIENT OF ACID MINE DRAINAGE IMPAIRMENT
Acid mine drainage (AMD) creates stressful conditions for stream organisms, including low pH and elevated dissolved metal concentrations. These conditions strongly influence stream communities, leading to low diversity and mostly tolerant taxa in AMD impaired streams. We hypothesized that impaired streams recover faster from streambed disturbance than recovered and unimpaired streams. Riffles were physically disturbed with rakes in AMD impaired streams (N=2), recovered streams (N=3), and unimpaired streams (N=2). Macroinvertebrates and periphyton were collected immediately before disturbance and 5, 10, 15, and 30 days afterwards in both undisturbed and experimentally disturbed areas. Macroinvertebrates were identified to family; chlorophyll a was quantified from scrubbed rocks. We used generalized mixed effects models to examine how AMD impairment and streambed disturbance affected the recovery rates of macroinvertebrate abundance and richness and chlorophyll a. Recovery in impaired sites was different than recovered and unimpaired sites for abundance (p<0.001 and = 0.002, respectively), richness (p>0.001 for both). Recovery of periphyton in impaired sites was significantly different than unimpaired sites (p<0.001), but not recovered sites (p=0.082). These findings suggest that recovered sites differ in recovery rate due to taxonomic characteristics, especially in the periphyton community.
Mariah Thrush Hood (Primary Presenter/Author), Ohio University, firstname.lastname@example.org;
Kelly Johnson (Co-Presenter/Co-Author), Ohio University, email@example.com;
Meg Beattie (Co-Presenter/Co-Author), Ohio University, firstname.lastname@example.org ;